Multiple transformer switching system



Fell 13, 1940f H. E. soMEs MULTIPLE TRANSFORMER SWTCHING SYSTEM 4 Sheets-Sheet l Filed Feb. 25, l 195'? Hlll @H @y E g Q H @j m R5 Y. E mm M O s O NE W 11D A m w O E 4 Sheets-Sheet 2 H. E. SOMES Filed Feb. 25, 1937 "MULTIPLE TRANSFORMER SWITCHING SYSTEM Feb. 13, 1940.

Feb.13, 1940. H. E. soMEs MULTIPLE TANSFORMER SWITCHING SYSTEM Filed Feb. A25, 1937 f 4 Sheets-Sheet 3 INVENTOR. HOWARDE. S omas ATTORNEY.

Feb. 13, 1940. H. E. soMx-:s

MULTIPLE TRANSFORMER SWITCHING SYSTEM Filed Feb.A 25. 1937 Sheets-Sheet 4 PIO@ Hr: Fuero HD n'u .g nUc HB JI HA i n'u Q M INVENTOR HOWARDE. Sowas ATTORNEY.

Patented Feb. 13,l 1940 UNITED y STATES PATENT OFFICE Howard E. Somea, Detroit, Mich.

Application February 25, 1937, Serial No. 127,668

10 anims.

in the form of transformers cut into and out of connection with the high frequency generator by means of individual primary and secondary switches. These switches have to be operated, nrst the primary and then the secondary switch, for each application and removal of treating power from the journal to be treated. This involves an application of switching apparatus with all of its uncertainties and heavy maintenance costs and with all of its deficiencies in the control of the timing of the heating period.

I have invented and disclosed in patent application Serial No. 96,929 a switching transformer which supplies current to the work coil directly from its secondary and which through a joint movement of the secondary into and out Yof transformer relation to the primary at the same time that the work coil is moved into and out of operative relation to the work, supples and removes the power to the work coil without theI making and breaking of either the primary orf the secondary circuit. Moreover, this transformer as well as the work coil is provided with a laminated magnetic core, whereby the efficiencies are vastly improved and it is made possible to carry immense power into extremely small spaces without loss of efficiency. Y

According to this invention I apply the switching transformer of my invention to an object like a crank shaft or engine block containing in one unit a number of portions such as bearings or engine cylinders to be heat treated in one jig position of the work with respect to a multiple number of heating units. In case, of course, a single heating Vunit is to be used the problem is quite different, involvingpas it does the relative shift between the heating unit and that product The solution of this prob1em I attain by the organization of a switching transformer inwhich there are provided a plurality of stationary secondary elements-and a single primary element which has a movement of translation in succession having a number of portions tobe' hea-t treated.

(ci. 21a-13) from one of the -secondaries to another and a dwell before each secondary and in full operative relation thereto suiilcient to supply during the dwell to the heating unit connected with the secondary, that energy required. Thereby I may use as many heating coils as there are portions in the product to be treated, bearings for example, or cylinders in a. cylinder block, for example, each provided and flxedly ,connected with its own secondary, and then shift the single primary of the transformer from one to another in succession.

In the accompanying drawings I illustrate that best embodiment of my invention now known toV me through the medium of the following figures.

Fig. 1 is a side view of the switching apparatus associated with a work piece.

Figs. 1a, lb,-and 1c show the left hand portion, central portion and right hand portion, respectively, of a longitudinal generally axial cross section of one unit of the switching mechanism in which are mounted three transformer secondaries.

Fig. 2 is a transaxial cross section showing this unit in juxtaposition to a mating unit adapted to operate upon multiple portions of the same work piece to be treated.

Fig. 3 is a right hand end view of one of the motor cylinders.

Fig. 4 is a transverse section of the motor cylinder, taken on the line 4-4 of Fig. 1c.

Figs. 5 to 9 are diagrams showing successive phases of operation.

'Ihe machine instead of being illustrated in connection with a six journal crankshaft is illustrated in connected with a six cylinder line engine block.

I is an elongated overhead frame which may be supported overhead by any appropriate number of uprights and braces not shown. II is the switching transformer unit in general, I2 the motor device for operating this switching transformer, and I3 is a camming device coacting with the motor device Hl to effect a variable spacing shift of the primary from one transformer to another, while Il are the heating units of which there is one for each transformer secondary and vone for each motor cylinder of the block I to be treated.

The transformer switching device as represented embodies six transformer secondaries I6, vthree in axial alignment with each of the axes I1 which are symmetrically located with respect to the plane Il of the heating units I4 and the wound upon the laminated magnetic cores I9 of annular form held together by the'annular end rings 20 which are clamped together upon them through the intermediary of a surrounding casing 2I to which the end rings are bolted. The secondary leads 22 extend radially outwardly toward the plane I8 and then along the plane I8 and to the heating coils 23. are rigid through the advance portion 24 of their lengths and flexible through the following portion 25, the flexible portions 25 are raised together so that the eiective length and general convolutions thereof are substantially unchanged during the axial reciprocations to the heating coils 23.

Reverting again to the switching unit II, it will be seen that in the length of the unit there is provided a space for two more `transformersecondaries, the three shown being in the center and contiguous to each other and the two extra spaces on each end. These eXtra spaces are occupied by dummy magnetic cores 26 also laminated and similarly clamped together. When the primary of the transformer reaches these cores the cores control the reactance thereof in a manner which will be described. The ensemble of the plurality of secondary transformer cores and dummy cores are carried within a tubular casing 21 within which they are clamped together in contiguity by means of end plates or caps 29 applied to the opposite ends of the tubular casing through bolts 30 which engage in lateral projecting end flanges 3l on the casing' 27.

T hese end caps 29 are provided with central bores 32 which are provided with bushings 33 affording bearing surfaces for mounted and reciprocable shaft or rod 34 which bears the transformer primary element 35 coacting with all of the switching transformers of the series. The shaft 34 is in two sections, the one section at the right adjoining the lmotor mechanism I2 being solid and connected with the core 36 of the transformer primary by means of a flange 31 which is through bolted as at 38 to the head 39 by means of which the laminations 40 of the core are bound together and about the central arbor 4I of the'core structure. Primary coil 35 in this case is exteriorly wound upon the core 40. 'I'he other part of the shaft 34 makes a similar connection through the same bolts 38 with the opposite end of the core, that to the left. On its part, however, it is hollow and receives in the hollow the primary leads 42 of the transformer which leads connect with the primary source of high frequency energy either a high frequency transformer or a high frequency generator. 'Ihis hollow shaft passes through thehead 29 on the left hand end of the casing and projects therebeyond a distance substantially equal .to the lengthof the switching unit itself and to that portion of the solid rod 34 required to project the transformer primary the full length of the cage.

The solid portion of the shaft 34 projecting from the right is provided on its end with an extension 43 of reduced diameter which becomes the piston rod of the iiuid pressure motor 44 and in connection with which it bears a piston 45 through which it is reciprocated with respect to the casing 44. 'I'his casing 43 is arranged in depending stop frame l2 passing vertically through which are a plurality7 of stops 46 spring ypressed upwardly by springs and depressed seriatim by a sequence of cams 48, whereby through rotation of cam shaft 49 which bears the cams (whichv rotation may. be achieved The conductors 22 an axially through a gear) eiects the sequential downward projection and retrogression of the stop pins 46. When depressed, the pins, as shown by that one on the extreme left, the rst of the series, have their tapered points 52 engaged in correspondingly -tapered sockets 53 in the upper portion of `the casing 44. The casing 44 is arranged in I 55 in much the same manner as is the cylinderY case 44 borne upon the under sideof the stop base I 2. Associated `with the stop base are a plurality of vertically arrangedi'stops 58 projected upwardly under the influence oi springs 59 and movable downwardly under the influence of sequential cams 60 driven by gear 59 which latter and gear 5I for driving the cams 48 are driven through a suitable positive driving connection from a synchronous alternating current electric motor not shown, whereby the cams of vthe two series are flxedly geared together. and

operate in a definite relative time sequence. When the camsdepress the stop pins 58 their lower extremities 6I engage successively in the single socket 62 provided in the outer extremity of the hollow shaft section 341.

Now observe that in connectionv with the single course of heating units I4 and the single work piece I5 to be treated, there are provided two series II of transformers, one set on each side of the plane of symmetry I8 in which the heating units I4 lie. operated by a system of motor and stop devices like that which has been described in connection with Fig. l. A timing controller commutator not shown will be provided to afford a sequence of operation through suitably arranged electrically controlled fluid pressure valves exemplified by the valve and control solenoid shown at 63 and 94, respectively, in Figs. 1c and 4. Connections of the valvesto the cylinders is through flexible leads as indicated.

The heating units I4 lying in the plane of symmetry I8 consist each of the coil 23 per se associated relatively movable and internally lam-` ating cylinder 6l bearing piston 68 through which, and piston rod 69 connecting with the coil 23, vthe coil 23, ring 65 and appurtenant parts are reciprocated vertically up and down to project the coil into and out of operational relation 'to the work. In my copending application Serial No.'.119,400, filed January 7, 1937, I`have generally designated such units as follows.v 'I'he heating unit 23 and adjunctive parts as H and the heating unit operating-cylinder 61 and appurtenant parts as H1. Similarly I have designated the transformer switching units I I as T. Such numerals are additionally generally applied here for the purpose of clarity and for the purpose of collaboration upon the detailed description of operation in case of need.

In this instance instead of being supported by an independent framework, the nlts described H and Hl are supported'from the same general horizontally extending overhead frame I0 as are the remaining units of the machine. Preferably Each one of these units II is andere as shown in Fig. 2 a unit casing'con'stitutes at one and the same time thetubular casing 21 and the general framework 89 through which the umts H are supported. The s'ame controller commutator through which the sequence of operation of the motor units 44 with relation to the cams is carried out should include control contact segments for the sequence operations of the units H1.

Likewise, this controller should carry controls for the quenching mechanisms.V These mechanisms, the quenching nozzle Q, the quenching motor unit Q1, and the supplemental quench control valve unit Q2 are arranged with respect to the units H and H1 in the same general axial relation which they occupy in my copending application aforesaid, and their relative functionings .are the same.

With reference particularly to Fig. 1 and to the diagrammatic showings of the successive operations contained in Figs. 5 to 9 the operation is as follows: At the outset when the sequency cams and the controller (not shown) have started to operate and the primary 35 being connected to its leads 42 with ak source of high frequency alternating current, and a source of uid pressure being connected with the two switch motor cylinders 44, the relation of the parts on both sides of the plane of symmetry I8 of the machine and as applying to both groups of switching transformers T is as shown in Figs. 1 and 2. This is to say that all switching transformers are off, that the primaries 35 are at the extreme left as are also the pistons 45, and that extreme left hand stops 45 and 58 are engaged respectively with the movable motor cylinders 44 and with the shifting left hand shaft end 341.

Upon the first exercise of cyclical control of the controller, iiuid pressure is admitted through solenoid valve 64 to the left hand end of the switching motor 44 on one side of the plane of symmetry I8, let us say the motor pertaining to the group of switching transformers T in the foreground which would be that on the right of Fig. 2.

The action which takes place is diagrammed in Fig. 5. In a fraction of a second approximately 1,45 of a second, for example, the piston 45 has been driven to the right to the extremity of cylinder 44 whereacushioned stop is effected by the reduced extension 1| engaging in the reduced cylinder extension 12 in a dash pot fashion, and stop pin 58 is engaged with the abutment socket 62 on the left hand end of shaft 341. Immediately prior to this, however, .and as the first operation of the controller, iuid pressure has been .admitted to the operating cylinder 61 to project heating unit 23 into the cylinder in position A in the wo'rk block I5, pilot device 1 engaging a suitable centering member 11 positioned at the bottom of the engine cylinder bore. The heating unit is therefore preliminarily in position for the heat treatment which is to follow. Incidentally with the` shift of the primary 35 intojuxtaposition with the first secondary to be energized, the coil 23 of the heating unit H is energized and thework is heated for the required brief period.'

After the moment of institution of this heating and Within the brief period it endures, the con-A troller removes pressure from the left hand end f of piston 45, cam shaft 49 permits the left hand stoppin 46 to lift under the yielding spring pressure of spring 41, and moves down toward engaging position a succeeding stop pin tothe right of the ilrst.l This results in'a shift to the right of the motor cylinder 44 operating the group of switching transformers T (now in action), and its coming to rest stopped by the newly `shifted pin 44. This is shownv diasrammaticaliy in Fig. 6. Also during this period of heating of the first cylinder the heating unit H in the position C has been dropped into working relation with respect to the cylinder in position C through admission of fluid pressures to its motor cylinder 61. 'I'his also is shown in Fig. 6.

The third phase of cyclical movement of the controller then releases the pressure from the right of piston 45 and again applies it to the left hand end of the kpiston with a resultant quick shift of the transformer primary from the ilrst secondary or that associated with cylinder in position A, to the next in series and associated with cylinder in position C, into which the pilot 1 vand work coil have been previously entered as shown in Fig. 6. IThis third phase is shown diagrammatically in Fig. 7. Cams 60 have operated seriatim to permit this second shift of piston 45 to achieve the second transformer switching operation', the left hand pin inengagement having been permitted to lift from its engagement by the cam andthe next succeeding right hand pin moved by the cam into engagement with the shaft and ready to slip into its socket 62 the moment piston 45 reached the right hand end of motor cylinder 44, and was given its cushion stop.

The next phase is, as respects .position E and the cylinder in that position, a repetition of those which have been described in connection with positions A and C. After the completion of the foregoing phases, as described in connection with positions A and C, in connection with position E, the next phase of the operation is directed to position B which involves operation of the second group of transformer elements to be found on the opposite side of the plane of symmetry i8 of the switching transformer machine. In this other half the phases of operation of the controller follow each other successively just as they have for the previous half. the phases of which have been described in detail. To make them entirely clear,.however, phase diagrams 8 and 9 have been added. Phase diagram 8 indicates the last heating phase of group No. 1 and the projection into cylinder in position B of the first heating unit H of group No. 2 to be ready for the next succeeding phase which is to eect the heating of such cylinder, the first of the alternate series of cylinders B, D, and F to be operated upon by this second half or group No. 2 of the transformer switching' machine. Fig. 9 diagrams the first phase complete in itself in connection with the second group, except that it is carried out wholly by the switching transformer devices connected with the second group only. It

will be observed by comparison'with Fig. 5 that y it is identical in operations withv the operations of the first phase of the rst group, that shown in Fig. 5. That is to say, fluid pressure has been admitted to the left of piston .45 of the motor 44 of this group and has shifted piston 45 to the right and moved the switching transformer primary 35 of transformer group No. 2 for the first time into transformer relation with a secondary II to the extreme left of group No. '2, that being the secondary associated with piston B.

-From this point on, the shifts are made as heretofore described, successively from position B to position D and to position F, treating successively cylinders B, D and F.

Quickly after the withdrawal of any movable primary element 35 from a given secondary element i6, the heating coil 23 associated with such secondary element is withdrawn from the cylinder bore just heated and the quenching head or nozzle Q associated with that cylinder bore moved upwardly into the bore by suitable operation of the motor cylinder Q1 and quenching iiuid supplied thereto through the electromagnetic valve 15, the operation of the apparatus elements involved being effected in proper timed relation by the controller in a manner well understood by those skilled in the art and similar to that described in my copending application Serial No. 119,400, flied January '7, 1937.

After the engine block l5 is completely treated, with all the heating coils 23 and quenching heads Q withdrawn, and the movable primary elements 35 and their motor cylinders and pistons M and at the extreme right with the primary elements 35 in the extreme right hand dummy secondary cores 26 such treated block is removed and an untreated block located in its place. The operation is then repeated in reverse order, that is with the primary transformer elements 35 moving back step-by-step from out the extreme right hand dummy core 2S into the extreme left hand dummy core 26, the cams I8 and 50 being provided with -two sets of projections one for left to right sequence and one for right to left sequence. Likewise, a second or alternate portion of the controller commutator is provided with a reverse arrangement of control contact segments for controlling the various electromagnetic valves for the motor cylinders and quenching fluid supply in reverse order.

To afford sufficient time for unloading and reloading of the cylinder blocks, the controller may be stopped between loadings or may, in any known or other sui-table manner be provided with a blank or idle time period at the beginning of which it is locked out of control and during which period only, it may be released for again taking control at the end of such period. Arrangements for eiiecting such a safety lock out are disc`osed in detail in my copending applications Serial No. 96,346, filed August 17, 1936, and Serial No. 119,400, led January 7, 1937.

While I have thus described a preferred embodiment of my invention by Way of example, it is to be understood that the invention is not limited in its application to such specific embodiment Abut contemplates'v all vsuch modifications and variants thereof as fall fairly within the scope of the appended claims. For example any known or other suitable form of motor means may be used for imparting the desired intermittent motion to the movable transformer element,

and various means other than that shown may be used for holding the movable transformer element in its different working positions.

I claim: Y

1. Apparatus for heat .tree/ting a plurality of different separate portions of a common work piece by high frequency heavy current electrom-agnetic induction which comprises a plurality of inductive heating coils one for each portion to be treated, a secondary transformer element connected in circuit with each heating coil, and a common primary transformer element telescopically arranged to move telescopically into and out of inductive relation with any one of said secondary transformer elements one at a time to the substantial exclusion of the remainder to effect energization of said-heating coils.

2. Apparatus for heat treating a plurality of different separate portions of a common work piece by high frequency heavy current electromagnetic induction which comprises a plurality of inductive heating coils one for each portion to be treated, a plurality of secondary transformer elements each connected in circuit with one of said heating coils, a pair of secondary magnetic core elements, said secondary tran-sformer elements and magnetic core elements being arranged in seriatim with one of the magnetic core elements at each end of the series, and a transformer primary element telescopically arranged to be moved telescopically from a position of inductive relation with one of lsaid magnetic core elements into inductive relation with said secondary ,transformer elements one at a time to the substantial exclusion of theremainder and said other magnetic core'element in seriatim in a continuous direction, whereby the electrical characteristics of the primary element may be maintained Without'undue variation.

' 3. Apparatus for heat treating a plurality of dlerent separate portions of a common Workpiece by high frequency heavy current electromagnetic induction Which comprises a plurality of inductive heating coils one for each portion to be treated, a plurality of secondary tran-sformer elements each connected in circuit with one of said heating coils and each provided with a partly closed magnetic core element, a transformer primary element having a partly closed magnetic core element telescopically arranged with respect to and yadapted to be closely coupled to any of said first mentioned core elements to bring the two transformer elements into transformer relation, and means for moving said common primary transformer element into transformer relation with any of said secondary transformer elements to the substantial exclusion o f the remainder.

4. The system as claimed in claim 3 in which the secondary elements are arranged in a row and provided with means for moving the primary element along the row into transformerA relation with each of said secondary elements in seriatim and a magnetic core element situated at each end of the row of secondary elements for maintaining the reluctance of the magnetic circuit of the primary element below a predetermined value upon movement of the primary element beyond either end of the row of secondary elements.

5. A multiple switching transformer apparatus comprising a plurality of secondary transformer elements arranged in a line, a primary transformer element arranged to be moved along said line into coupled relation with said secondary elements, and means for moving said primary element along said line comprising an abutment element arranged to be moved in relation to said primary coil, means for moving said primary coil in relation to said abutment element, and means for locking said abutment element and said primary coil moving means against movement.

6. A multiple transformer switching apparatus comprising a plurality of secondary transformer elements aligned in fixed spaced relation, a trackway extending parallel to the direction of alignment of said secondary elements, a iiuid pressure work cylinder mounted to travel along said trackway, a work piston in said cylinder, a primary transformer element,v means for transmitting motion from the work piston to the primary element to move the primary elementinto transformer relation with said secondary elements along their line of extension, means for locking the piston in xed relation to said secondary elements, means for locking the work cylinder in relation to said secondary elements and means for admitting and exhausting iiuid under pressure to and from the work cylinder on opposite sides of the piston whereby the piston and work cylinder may be moved each in relation to the secondary elements whenthe other is locked in relation to the secondary elements for moving the primary element in relation to said secondary elements.

7. A multiple switching transformer for supplying high frequencyheavy current energy for heat treatment comprising a plurality of stationary secondary elements, a single primary element having a movement of translation in succession from one of the secondaries to another, and means for intermittently moving the primary step by step from one secondary to another in one continuous direction throughout its movement of translation into cooperative relation and coaxial alignment with said secondary elements one at a time in succession to the substantial exclusion of the remainder. Y

8. Apparatus for heat treating as in claim 1 comprising means for maintaining the inductive reactance of said primary element above a predetermined value while out oi operative relation with of said secondary elements.

9. An apparatus for heat treating a plurality of different separate portions of a common worki5 piece by high frequency heavy current electromagnetic induction which comprises a plurality of inductive heating coils, one for each portion to be treated, means for moving the heating coils into and out of operative relation with their respective portions of the work-piece at different times, a plurality of secondary transformer elements, one connected in circuit with each heating coil, and a common primary transformer element telescopically arranged to move telescopically into and out of inductive relation with anyone of said secondary transformer elements to the substantial exclusion ofthe remainder to eiect energization of said heating coils only while the associated heating coil of that one secondary element which is in operative relation with its respective portion of the work-piece.

l0. Apparatus for heat treating a plurality of different separate portions of a common work piece by high frequency heavy current electromagnetic induction which comprises a plurality of inductive heating coils one for each portion to be treated, a secondary transformer element connected in circuit with each heating coil, and a common primary transformer element adapted l to be arranged coaxially with each secondary element and arranged to move into andout of induction relation with any one of said secondary transformer elements, one at a time to the substantial exclusion of the remainder to effect en- 30 ergization of said heating coils.

HOWARD E. HOMES. 

